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101.
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Johnson RD Lewis RJ Canfield DV Dubowski KM Blank CL 《Journal of forensic sciences》2005,50(3):670-675
Specimens from fatal aviation accident victims are submitted to the FAA Civil Aerospace Medical Institute for toxicological analysis. During toxicological evaluations, ethanol analysis is performed on all cases. Care must be taken when interpreting a positive ethanol result due to the potential for postmortem ethanol formation. Several indicators of postmortem ethanol formation exist; however, none are completely reliable. The consumption of ethanol has been shown to alter the concentration of two major serotonin metabolites, 5-hydroxytryptophol (5-HTOL) and 5-hydroxyindole-3-acetic acid (5-HIAA). While the 5-HTOL/5-HIAA ratio is normally very low, previous studies using living subjects have demonstrated that the urinary 5-HTOL/5-HIAA ratio is significantly elevated for 11-19 h after acute ethanol ingestion. Recently, our laboratory developed and validated an analytical method for the simultaneous determination of both 5-HTOL and 5-HIAA in forensic urine samples using a simple liquid/liquid extraction and LC/MS/MS and LC/MS/MS/MS. In this previous work a 15 pmol/nmol serotonin metabolite ratio cutoff was established in postmortem urine, below which it could be conclusively determined that no recent antemortem ethanol consumption had occurred. In the current study this newly validated analytical method was applied to five ethanol-positive aviation fatalities where the origin of the ethanol present could not previously be conclusively determined. In four of the five cases examined the detected ethanol was demonstrated to be present due to postmortem microbial formation, and not consumption, even though some indication of ethanol consumption may have been present. 相似文献
104.
Despite recent and growing media attention surrounding obesity in the United States, the so-called obesity epidemic remains a highly contested scientific and social fact. This article examines the contemporary obesity debate through systematic examination of the claims and claimants involved in the controversy. We argue that four primary groups-antiobesity researchers, antiobesity activists, fat acceptance researchers, and fat acceptance activists-are at the forefront of this controversy and that these groups are fundamentally engaged in framing contests over the nature and consequences of excess body weight. While members of the fat acceptance groups embrace a body diversity frame, presenting fatness as a natural and largely inevitable form of diversity, members of the antiobesity camp frame higher weights as risky behavior akin to smoking, implying that body weight is under personal control and that people have a moral and medical responsibility to manage their weight. Both groups sometimes frame obesity as an illness, which limits blame by suggesting that weight is biologically or genetically determined but simultaneously stigmatizes fat bodies as diseased. While the antiobesity camp frames obesity as an epidemic to increase public attention, fat acceptance activists argue that concern over obesity is distracting attention from a host of more important health issues for fat Americans. We examine the strategies claimants use to establish their own credibility or discredit their opponents, and explain how the fat acceptance movement has exploited structural opportunities and cultural resources created by AIDS activism and feminism to wield some influence over U.S. public health approaches. We conclude that notions of morality play a central role in the controversy over obesity, as in many medical disputes, and illustrate how medical arguments about body weight can be used to stymie rights claims and justify morality-based fears. 相似文献
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In pursuing their goals, members of the U.S. Supreme Court areaffected by their institutional setting. How has that institutionalenvironment changed over time and what have been the politicalconsequences of those changes? Despite considerable analysisof the institutional dynamics of legislatures and executives,political scientists have been slow to bring time series techniquesto the study of the Supreme Court, and as a result much lessis known about its evolutionary path. Measuring a variety oforganizational characteristics, I construct an index of theinstitutionalization of the Supreme Court from 1790 to 1996.This indicator suggests that the integration of the Court intothe system of federal policy making has better enabled the justicesto satisfy their objectives. To demonstrate this empirically,I test a series of error correction models of judicial influence,each of which confirms that the nature of the Supreme Court'scharacter has had considerable implications for the scope ofthe justices' legal and political impact. These results underscorethe need for judicial scholars to examine the Court's policymaking in longitudinal perspective. 相似文献
107.
The purpose of this study was to evaluate the ability of two amphetamine class screening reagents to exclude ephedrine (EPH), pseudoephedrine (PSEPH), and phenylpropanolamine (PPA) from falsely producing positive immunoassay screening results. The study also sought to characterize the prevalence and concentration distributions of EPH, PSEPH, and PPA in samples that produced positive amphetamine screening results. Approximately 27,400 randomly collected human urine samples from Navy and Marine Corps members were simultaneously screened for amphetamines using the DRI and Abuscreen online immunoassays at a cutoff concentration of 500 ng/mL. All samples that screened positive were confirmed for amphetamine (AMP), methamphetamine (MTH), 3,4-Methylenedioxyamphetamine (MDA), 3,4-Methylenedioxymethamphetamine (MDMA), EPH, PSEPH, and PPA by gas chromatography/mass spectrometry (GC/MS). The DRI AMP immunoassay identified 1,104 presumptive amphetamine positive samples, of which only 1.99% confirmed positive for the presence of AMP, MTH, MDA, or MDMA. In contrast, the online AMP reagent identified 317 presumptive amphetamine positives with a confirmation rate for AMP, MTH, MDA, or MDMA of 7.94%. The presence of EPH, PSEPH, or PPA was confirmed in 833 of the 1,104 samples that failed to confirm positive for AMP, MTH, MDA, or MDMA; all of the 833 samples contained PSEPH. When compared to the entire screened sample set, PSEPH was present in approximately 3%, EPH in 0.9%, and PPA in 0.8% of the samples. The results indicate that cross reactivities for EPH, PSEPH, and PPA are greater than reported by the manufacturer of these reagents. The distribution of concentrations indicates that very large concentrations of EPH, PSEPH, and PPA are common. 相似文献
108.
Accident investigation is frequently cited as the cornerstone of an effective occupational health and safety program. We suggest that the literature on accident investigation is based on a model of witnesses as neutral and accurate recording devices. The literature on eyewitness testimony and criminal investigation offers strikingly different conclusions. We review these findings and point to their implication for research on accident investigation in occupational health and safety contexts. 相似文献
109.
Sharma AN Nelson LS Hoffman RS 《The American journal of forensic medicine and pathology》2004,25(2):156-158
The neurologic manifestations of thallium poisoning include a severely painful ascending peripheral neuropathy, autonomic dysfunction, cranial nerve abnormalities, and a toxic encephalopathy. Although thallium has a short half-life, these neurologic manifestations commonly progress, even as the blood concentration of thallium decreases. This suggests either that thallium persists in neuronal tissues or that it initiates an injury cascade that takes time to fully manifest. As the latter mechanism is consistent with many toxin exposures, the concept of a central nervous system reservoir for thallium is often discounted. A recent case provided a unique opportunity to evaluate this possibility. A 48-year-old man was acutely and chronically thallium poisoned by his common-law wife. During his initial exposures, only gastrointestinal symptoms manifested. Following an acute ingestion, hospitalization was required. Over 3 days, his symptoms rapidly progressed from a severely painful neuropathy to slurred speech, ptosis, confusion, coma, respiratory insufficiency, and death. Because of considerations of alternative diagnoses, 2 lumbar punctures were performed, one on admission and another on the day of his death. Serum thallium concentrations obtained from stored blood samples were paired with spinal fluid concentrations from the same days. On day 1, serum and spinal fluid concentrations were 8700 mu/L and 1200 mu/L, respectively. On day 3, although the serum concentration had fallen to 7200 mu/L, the spinal fluid concentration had increased to 2100 mu/L. This case provides evidence to support the hypothesis that thallium distributes into the central nervous system more slowly than the blood compartment, and this may in part account for the progression of neurologic findings in the setting of decreasing serum concentrations. 相似文献
110.
McCusker PJ Moran MJ Serfass L Peterson KH 《International journal of offender therapy and comparative criminology》2003,47(5):585-596
Relationships among Structured Interview of Reported Symptoms (SIRS) scores and Minnesota Multiphasic Personality Inventory--2 (MMPI-2) F(p) and F scores were examined for 63 suspected malingerers evaluated at either of two psychiatric facilities. Despite differences between facilities in terms of seriousness of subjects' offenses, mean scores on the malingering tests were similar. Cutting scores for F(p) and F resulting in substantial correspondence between these scales and the SIRS were derived. Use of the cut score for F(p) proposed by Arbisi and Ben-Porath (1995) resulted in less agreement with the SIRS than did a lower cut score. No substantial difference between F(p) and F in each scale's overall agreement with the SIRS was observed. A principal components analysis of the SIRS primary scales produced two factors, interpreted as Overreporting of Symptoms and Implausible Symptoms. F(p) was observed to correlate significantly with Implausible Symptoms but not with Overreporting of Symptoms; F was significantly correlated with both factors. 相似文献